Limits of Exogenous Fibrolytic Enzymes to Improve Digestion and Intake of a Tropical Grass

The effect of the addition of exogenous fibrolytic enzymes (mainly xylanase and cellulase activities, 15 ml/15 kg of fresh forage), on intake, total tract digestibility and nylon bag degradability of a chopped fresh Digitaria decumbens grass was studied at 2 stages of regrowth ( 21 and 56-day old grasses). Moreover, comparisons between ground and chopped grass were done using the nylon bag degradability method. DM intake (g/kg BW0.75) and organic matter total tract digestibility for control and enzyme treatments respectively were 69.1 vs. 65.9 (p>0.05) and 0.723 vs. 0.727 (p>0.05) with the 21-day old regrowth. Based on the same parameters, values for the 56-day old grass were 58.1 vs. 52.7 (p>0.05) and 0.621 vs. 0.591 (p>0.05). Nylon bag degradation at 24 h of the dry matter for control versus enzyme treatments were 0.653 vs. 0.70 (p0.05) with the 21-day old regrowth. Based on the same parameters, values for the 56-day old grass were 58.1 vs. 52.7 (p>0.05) and 0.621 vs. 0.591 (p>0.05). Nylon bag degradation at 24 h of the dry matter for control versus enzyme treatments were 0.653 vs. 0.70 (p